/*
   * Generic Macintosh NCR5380 driver
   *
   * Copyright 1998, Michael Schmitz <mschmitz@lbl.gov>
   *
   * derived in part from:
   */
  /*
   * Generic Generic NCR5380 driver
   *
   * Copyright 1995, Russell King

   */

  #include <linux/types.h>

  #include <linux/module.h>

  #include <linux/ioport.h>
  #include <linux/init.h>
  #include <linux/blkdev.h>
  #include <linux/interrupt.h>

  #include <linux/platform_device.h>

  #include <asm/hwtest.h>

  #include <asm/io.h>

  #include <asm/macints.h>

  #include <asm/setup.h>

  #include <scsi/scsi_host.h>

  
  /* Definitions for the core NCR5380 driver. */

  #define PSEUDO_DMA

  #define NCR5380_implementation_fields   unsigned char *pdma_base

  #define NCR5380_read(reg)               macscsi_read(instance, reg)
  #define NCR5380_write(reg, value)       macscsi_write(instance, reg, value)

  
  #define NCR5380_pread                   macscsi_pread
  #define NCR5380_pwrite                  macscsi_pwrite

  #define NCR5380_dma_xfer_len(instance, cmd, phase)	(cmd->transfersize)

  
  #define NCR5380_intr                    macscsi_intr
  #define NCR5380_queue_command           macscsi_queue_command
  #define NCR5380_abort                   macscsi_abort
  #define NCR5380_bus_reset               macscsi_bus_reset
  #define NCR5380_info                    macscsi_info
  #define NCR5380_show_info               macscsi_show_info
  #define NCR5380_write_info              macscsi_write_info

  #include "NCR5380.h"

  static int setup_can_queue = -1;

  module_param(setup_can_queue, int, 0);

  static int setup_cmd_per_lun = -1;

  module_param(setup_cmd_per_lun, int, 0);

  static int setup_sg_tablesize = -1;

  module_param(setup_sg_tablesize, int, 0);

  static int setup_use_pdma = -1;

  module_param(setup_use_pdma, int, 0);

  static int setup_use_tagged_queuing = -1;

  module_param(setup_use_tagged_queuing, int, 0);

  static int setup_hostid = -1;

  module_param(setup_hostid, int, 0);

  static int setup_toshiba_delay = -1;
  module_param(setup_toshiba_delay, int, 0);

  /*
   * NCR 5380 register access functions
   */

  static inline char macscsi_read(struct Scsi_Host *instance, int reg)

  {

  	return in_8(instance->base + (reg << 4));

  }

  static inline void macscsi_write(struct Scsi_Host *instance, int reg, int value)

  {

  	out_8(instance->base + (reg << 4), value);

  }

  #ifndef MODULE
  static int __init mac_scsi_setup(char *str)
  {

  	int ints[8];

  
  	(void)get_options(str, ARRAY_SIZE(ints), ints);

  	if (ints[0] < 1) {
  		pr_err("Usage: mac5380=<can_queue>[,<cmd_per_lun>[,<sg_tablesize>[,<hostid>[,<use_tags>[,<use_pdma>[,<toshiba_delay>]]]]]]
  ");

  		return 0;

  	}

  	if (ints[0] >= 1)
  		setup_can_queue = ints[1];
  	if (ints[0] >= 2)
  		setup_cmd_per_lun = ints[2];
  	if (ints[0] >= 3)
  		setup_sg_tablesize = ints[3];
  	if (ints[0] >= 4)
  		setup_hostid = ints[4];
  	if (ints[0] >= 5)
  		setup_use_tagged_queuing = ints[5];
  	if (ints[0] >= 6)

  		setup_use_pdma = ints[6];

  	if (ints[0] >= 7)
  		setup_toshiba_delay = ints[7];

  	return 1;
  }
  
  __setup("mac5380=", mac_scsi_setup);

  #endif /* !MODULE */

  #ifdef PSEUDO_DMA

  /* 
     Pseudo-DMA: (Ove Edlund)
     The code attempts to catch bus errors that occur if one for example
     "trips over the cable".
     XXX: Since bus errors in the PDMA routines never happen on my 
     computer, the bus error code is untested. 
     If the code works as intended, a bus error results in Pseudo-DMA 

     being disabled, meaning that the driver switches to slow handshake.

     If bus errors are NOT extremely rare, this has to be changed. 
  */
  
  #define CP_IO_TO_MEM(s,d,len)				\
  __asm__ __volatile__					\
      ("    cmp.w  #4,%2
  "				\
       "    bls    8f
  "					\
       "    move.w %1,%%d0
  "				\
       "    neg.b  %%d0
  "				\
       "    and.w  #3,%%d0
  "				\
       "    sub.w  %%d0,%2
  "				\
       "    bra    2f
  "					\
       " 1: move.b (%0),(%1)+
  "				\
       " 2: dbf    %%d0,1b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #5,%%d0
  "				\
       "    bra    4f
  "					\
       " 3: move.l (%0),(%1)+
  "				\
       "31: move.l (%0),(%1)+
  "				\
       "32: move.l (%0),(%1)+
  "				\
       "33: move.l (%0),(%1)+
  "				\
       "34: move.l (%0),(%1)+
  "				\
       "35: move.l (%0),(%1)+
  "				\
       "36: move.l (%0),(%1)+
  "				\
       "37: move.l (%0),(%1)+
  "				\
       " 4: dbf    %%d0,3b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #2,%%d0
  "				\
       "    and.w  #7,%%d0
  "				\
       "    bra    6f
  "					\
       " 5: move.l (%0),(%1)+
  "				\
       " 6: dbf    %%d0,5b
  "				\
       "    and.w  #3,%2
  "				\
       "    bra    8f
  "					\
       " 7: move.b (%0),(%1)+
  "				\
       " 8: dbf    %2,7b
  "				\
       "    moveq.l #0, %2
  "				\
       " 9: 
  "						\
       ".section .fixup,\"ax\"
  "				\
       "    .even
  "					\
       "90: moveq.l #1, %2
  "				\
       "    jra 9b
  "					\
       ".previous
  "					\
       ".section __ex_table,\"a\"
  "			\
       "   .align 4
  "					\
       "   .long  1b,90b
  "				\
       "   .long  3b,90b
  "				\
       "   .long 31b,90b
  "				\
       "   .long 32b,90b
  "				\
       "   .long 33b,90b
  "				\
       "   .long 34b,90b
  "				\
       "   .long 35b,90b
  "				\
       "   .long 36b,90b
  "				\
       "   .long 37b,90b
  "				\
       "   .long  5b,90b
  "				\
       "   .long  7b,90b
  "				\
       ".previous"					\
       : "=a"(s), "=a"(d), "=d"(len)			\
       : "0"(s), "1"(d), "2"(len)				\
       : "d0")

  static int macscsi_pread(struct Scsi_Host *instance,
                           unsigned char *dst, int len)

  {

  	struct NCR5380_hostdata *hostdata = shost_priv(instance);

  	unsigned char *d;
  	unsigned char *s;

  	s = hostdata->pdma_base + (INPUT_DATA_REG << 4);

  	d = dst;
  
  	/* These conditions are derived from MacOS */
  
  	while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) &&
  	       !(NCR5380_read(STATUS_REG) & SR_REQ))
  		;
  
  	if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) &&
  	    (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH)) {
  		pr_err("Error in macscsi_pread
  ");
  		return -1;
  	}
  
  	CP_IO_TO_MEM(s, d, len);
  
  	if (len != 0) {
  		pr_notice("Bus error in macscsi_pread
  ");
  		return -1;
  	}
  
  	return 0;

  }
  
  
  #define CP_MEM_TO_IO(s,d,len)				\
  __asm__ __volatile__					\
      ("    cmp.w  #4,%2
  "				\
       "    bls    8f
  "					\
       "    move.w %0,%%d0
  "				\
       "    neg.b  %%d0
  "				\
       "    and.w  #3,%%d0
  "				\
       "    sub.w  %%d0,%2
  "				\
       "    bra    2f
  "					\
       " 1: move.b (%0)+,(%1)
  "				\
       " 2: dbf    %%d0,1b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #5,%%d0
  "				\
       "    bra    4f
  "					\
       " 3: move.l (%0)+,(%1)
  "				\
       "31: move.l (%0)+,(%1)
  "				\
       "32: move.l (%0)+,(%1)
  "				\
       "33: move.l (%0)+,(%1)
  "				\
       "34: move.l (%0)+,(%1)
  "				\
       "35: move.l (%0)+,(%1)
  "				\
       "36: move.l (%0)+,(%1)
  "				\
       "37: move.l (%0)+,(%1)
  "				\
       " 4: dbf    %%d0,3b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #2,%%d0
  "				\
       "    and.w  #7,%%d0
  "				\
       "    bra    6f
  "					\
       " 5: move.l (%0)+,(%1)
  "				\
       " 6: dbf    %%d0,5b
  "				\
       "    and.w  #3,%2
  "				\
       "    bra    8f
  "					\
       " 7: move.b (%0)+,(%1)
  "				\
       " 8: dbf    %2,7b
  "				\
       "    moveq.l #0, %2
  "				\
       " 9: 
  "						\
       ".section .fixup,\"ax\"
  "				\
       "    .even
  "					\
       "90: moveq.l #1, %2
  "				\
       "    jra 9b
  "					\
       ".previous
  "					\
       ".section __ex_table,\"a\"
  "			\
       "   .align 4
  "					\
       "   .long  1b,90b
  "				\
       "   .long  3b,90b
  "				\
       "   .long 31b,90b
  "				\
       "   .long 32b,90b
  "				\
       "   .long 33b,90b
  "				\
       "   .long 34b,90b
  "				\
       "   .long 35b,90b
  "				\
       "   .long 36b,90b
  "				\
       "   .long 37b,90b
  "				\
       "   .long  5b,90b
  "				\
       "   .long  7b,90b
  "				\
       ".previous"					\
       : "=a"(s), "=a"(d), "=d"(len)			\
       : "0"(s), "1"(d), "2"(len)				\
       : "d0")

  static int macscsi_pwrite(struct Scsi_Host *instance,
                            unsigned char *src, int len)

  {

  	struct NCR5380_hostdata *hostdata = shost_priv(instance);

  	unsigned char *s;
  	unsigned char *d;

  	s = src;

  	d = hostdata->pdma_base + (OUTPUT_DATA_REG << 4);

  
  	/* These conditions are derived from MacOS */
  
  	while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) &&
  	       (!(NCR5380_read(STATUS_REG) & SR_REQ) ||
  	        (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH)))
  		;
  
  	if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ)) {
  		pr_err("Error in macscsi_pwrite
  ");
  		return -1;
  	}
  
  	CP_MEM_TO_IO(s, d, len);
  
  	if (len != 0) {
  		pr_notice("Bus error in macscsi_pwrite
  ");
  		return -1;
  	}
  
  	return 0;
  }
  #endif

  #include "NCR5380.c"

  #define DRV_MODULE_NAME         "mac_scsi"
  #define PFX                     DRV_MODULE_NAME ": "
  
  static struct scsi_host_template mac_scsi_template = {

  	.module			= THIS_MODULE,
  	.proc_name		= DRV_MODULE_NAME,
  	.show_info		= macscsi_show_info,
  	.write_info		= macscsi_write_info,
  	.name			= "Macintosh NCR5380 SCSI",
  	.info			= macscsi_info,
  	.queuecommand		= macscsi_queue_command,
  	.eh_abort_handler	= macscsi_abort,
  	.eh_bus_reset_handler	= macscsi_bus_reset,
  	.can_queue		= 16,
  	.this_id		= 7,
  	.sg_tablesize		= SG_ALL,
  	.cmd_per_lun		= 2,
  	.use_clustering		= DISABLE_CLUSTERING,

  	.cmd_size		= NCR5380_CMD_SIZE,

  	.max_sectors		= 128,

  };

  static int __init mac_scsi_probe(struct platform_device *pdev)
  {
  	struct Scsi_Host *instance;
  	int error;
  	int host_flags = 0;
  	struct resource *irq, *pio_mem, *pdma_mem = NULL;
  
  	pio_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (!pio_mem)
  		return -ENODEV;
  
  #ifdef PSEUDO_DMA
  	pdma_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
  #endif
  
  	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
  
  	if (!hwreg_present((unsigned char *)pio_mem->start +
  	                   (STATUS_REG << 4))) {
  		pr_info(PFX "no device detected at %pap
  ", &pio_mem->start);
  		return -ENODEV;
  	}
  
  	if (setup_can_queue > 0)
  		mac_scsi_template.can_queue = setup_can_queue;
  	if (setup_cmd_per_lun > 0)
  		mac_scsi_template.cmd_per_lun = setup_cmd_per_lun;
  	if (setup_sg_tablesize >= 0)
  		mac_scsi_template.sg_tablesize = setup_sg_tablesize;
  	if (setup_hostid >= 0)
  		mac_scsi_template.this_id = setup_hostid & 7;

  	if (setup_use_pdma < 0)
  		setup_use_pdma = 0;
  
  	instance = scsi_host_alloc(&mac_scsi_template,
  	                           sizeof(struct NCR5380_hostdata));
  	if (!instance)
  		return -ENOMEM;
  
  	instance->base = pio_mem->start;
  	if (irq)
  		instance->irq = irq->start;
  	else
  		instance->irq = NO_IRQ;
  
  	if (pdma_mem && setup_use_pdma) {
  		struct NCR5380_hostdata *hostdata = shost_priv(instance);
  
  		hostdata->pdma_base = (unsigned char *)pdma_mem->start;
  	} else
  		host_flags |= FLAG_NO_PSEUDO_DMA;

  #ifdef SUPPORT_TAGS
  	host_flags |= setup_use_tagged_queuing > 0 ? FLAG_TAGGED_QUEUING : 0;
  #endif

  	host_flags |= setup_toshiba_delay > 0 ? FLAG_TOSHIBA_DELAY : 0;

  	error = NCR5380_init(instance, host_flags);
  	if (error)
  		goto fail_init;

  
  	if (instance->irq != NO_IRQ) {
  		error = request_irq(instance->irq, macscsi_intr, IRQF_SHARED,
  		                    "NCR5380", instance);
  		if (error)
  			goto fail_irq;
  	}

  	NCR5380_maybe_reset_bus(instance);

  	error = scsi_add_host(instance, NULL);
  	if (error)
  		goto fail_host;
  
  	platform_set_drvdata(pdev, instance);
  
  	scsi_scan_host(instance);
  	return 0;
  
  fail_host:
  	if (instance->irq != NO_IRQ)
  		free_irq(instance->irq, instance);
  fail_irq:
  	NCR5380_exit(instance);

  fail_init:

  	scsi_host_put(instance);
  	return error;
  }
  
  static int __exit mac_scsi_remove(struct platform_device *pdev)
  {
  	struct Scsi_Host *instance = platform_get_drvdata(pdev);
  
  	scsi_remove_host(instance);
  	if (instance->irq != NO_IRQ)
  		free_irq(instance->irq, instance);
  	NCR5380_exit(instance);
  	scsi_host_put(instance);
  	return 0;
  }
  
  static struct platform_driver mac_scsi_driver = {
  	.remove = __exit_p(mac_scsi_remove),
  	.driver = {
  		.name	= DRV_MODULE_NAME,

  	},
  };

  module_platform_driver_probe(mac_scsi_driver, mac_scsi_probe);

  MODULE_ALIAS("platform:" DRV_MODULE_NAME);

  MODULE_LICENSE("GPL");